1. Field of the Invention
The invention relates in general to a saturation adjusting method, and more particularly to a method for adjusting saturation of a single color system.
2. Description of the Related Art
As for general users, the quality of a digital color image captured by a digital camera depends on the colorfulness of the digital color image. Hence, the quality of the digital color image for a general user substantially only depends on the colorfulness of the digital color image.
Accordingly, to adjust the colorfulness (i.e., saturation) of a digital color image becomes an important aim for the digital camera manufacturers. In the prior art method, the R, G, B values of each pixel in the digital color image is converted into the Y, Cb, Cr values, which serve as the data for adjusting the brightness (Y) and chroma (Cb, Cr), respectively.
However, the prior art method for adjusting the pixel saturation usually directly adjusts Cb, Cr chroma values of overall pixels after converting the R, G, B values of each pixel into the Y, Cb, Cr values, respectively. When the Cb, Cr values of each pixel in the digital color image are being directly adjusted, the saturation of each pixel is also adjusted simultaneously. Because the adjusted saturation of each pixel may influence one another, the color of the overall pixels of this digital color image is changed accordingly.
Therefore, the prior art method of adjusting the saturation of the pixels results in the color deviation of the final and overall pixels of the digital color image. In addition, even if the color deviation is not too large, the saturation of the final and overall pixels still has been adjusted and thus the color contrasts between the overall pixels cannot be enhanced. Hence, the adjusted color saturation effect is poor.